PCOS Therapy

and Lilliana Ciotta1

(1)
Obstetrics and Gynecological Pathology, P.O. “S. Bambino”, University of Catania, Catania, Italy
 
Keywords
DietExerciseMetforminInositolStatinsAntioxidantsGlucomannan
Gynecologists usually treat PCOS only as an endocrine disorder, without recognition of the very important part that insulin resistance plays in the syndrome.
In this section, the way to treat PCOS from a metabolic point of view, without dwelling on the use of oral contraceptives and antiandrogen drugs, will be discussed.
Lifelong strategies that improve the care of women with PCOS are essential, because of the chronic nature of the syndrome and the young age at which all the symptoms begin to manifest [1].
A valid therapeutic protocol for PCOS includes diet, physical exercise, and insulin-sensitizing agents such as metformin and inositol.
For example, in fact, a normal BMI is associated with a positive fertility outcome, and fertility specialists recommend achieving this BMI before IVF (in vitro fertilization): in fact, these techniques are invasive and expensive and have low success rates, so it seems logical to improve BMI and to support hormonal balance through diet, exercise, and nutrition supplements [2].

6.1 Diet and Exercise

As explained previously, a few evolutionary biologists suppose that many genetic hormonal tendencies contributing to PCOS have their origin in the switch from the pre-agrarian age diet to the current diet. The rapidly increasing rates of diabetes, heart disease, and PCOS coincide with the rapid changes in the modern human diet [2].
All women suffering from PCOS benefit from dietary therapy and exercise; in fact, dietary and lifestyle interventions are considered among the first-line treatments for PCOS.
There is no PCOS diet that will reverse the syndrome, but there are several dietary principles that a patient should follow to improve the symptoms.
Weight reduction leads to improvements of insulin sensitivity [3] and lipid profile [4]; it ameliorates hyperandrogenism (SHBG increase, FAI and testosterone decrease) and menstrual cycle rhythm [4–6], with reductions in adiposity from the truncal–abdominal area [5]. Moreover, there is evidence that these changes exert important beneficial effects also in the longer term on disorders such as type II diabetes mellitus, cardiovascular disease, and certain cancers (endometrial, breast, and colon cancer), compared with weight loss alone [7–9].
In most of the dietary studies in women with PCOS, improvements in metabolic and reproductive outcomes have been closely related to improvements in insulin sensitivity, suggesting that dietary modification (qualitative and quantitative) designed to improve insulin resistance may produce greater benefits than those achieved by energy restriction alone [7].
Clinicians prescribing lifestyle modifications must consider the patient’s capacity to sustain diet and exercise adherence and weight maintenance over time for the clinical benefits on PCOS to continue.
Considering how difficult it is for many patients to change their lifestyle, pharmaceutical modification of weight control could be an additional necessary therapeutic tool, such as the lipase inhibitor orlistat [10].
In some studies on overweight and obese women with PCOS, the use of orlistat has demonstrated an improvement in both metabolic and hormonal parameters [11, 12].
Orlistat is an antiobesity drug with minimal systemic absorption, and therefore, any effect of this drug is a result of weight loss and not the direct effect on ovaries.
The proposal therapeutic dose is 120 mg three times daily, before each meal, for 3 months, during which the patient must be able to lose at least 5 % of its total weight.

6.1.1 PCOS Dietary Recommendations

1.
Reduce total calories consumed to standard levels for sex, age, and activity: calories requests are higher for women with higher BMI and increase in relation to activity. It is often useful to initially focus on the eating pattern and the macronutrient content of the diet rather than to try to promote both healthy eating and weight loss too quickly [8]. Energy consumption can be reached by limiting nutrient intake or by increasing calories expenditure.
A daily calories deficit of 200 kcal/day will prevent weight gain; a deficit of 500 kcal/day is needed for the average person to lose 0.5 kg/week, while a 1,000 kcal deficit is needed for 1 kg weight loss/week [8].
 
2.
Reduce refined carbohydrates in favor of complex carbohydrates. “Refined” carbohydrates refer to a carbohydrate-based food that has been processed to strip it of some of its original fiber and unpackaged to produce a more “refined” product. For example, sugar cane and corn on the cob are whole foods, but the table sugar that is processed out of sugar cane and the cornstarch or high fructose corn syrup processed out of the corn are some refined carbohydrates [2].
A period of relatively strict carbohydrate restriction helps at the beginning of the diet; a recent study demonstrated that a reduced-carbohydrate diet results in lower measures of β-cell responsiveness and circulating insulin (27 % reduction in fasting insulin) when compared with a standard higher-carbohydrate diet [13].
Other studies have reported improvements in LDL cholesterol particle size, LDL concentration, and postprandial blood lipid profile [14–16].
On the other hand, low-carbohydrate diets have been associated with deleterious effects on lipid profile when used long term [17], and so severe carbohydrate restriction should be use as a short-term measure to achieve weight loss [8].
 
3.
Eat low-glycemic index (GI) foods: a few studies have shown that a low-GI diet can improve insulin resistance as well as many of its metabolic consequences including increasing HDL and plasminogen activator inhibitor-1 levels [18, 19]. Moreover, several epidemiological studies have also associated a low-GI diet with reduced risk of CVD and type II diabetes [20, 21].
A high-GI diet, on the other hand, has been shown to worsen postprandial insulin resistance [22]: in fact, a recent study showed that a low-GI diet improves insulin sensitivity and menstrual regularity more than a conventional healthy, moderate- to high-GI diet despite similar weight loss [23].
 
4.
Increase fiber to improve glucose regulation: fiber helps to slow the digestion of carbohydrates and improves insulin resistance [24, 25].
 
5.
Increase high–protein foods: it was demonstrated that proteins consumed at breakfast (compared with lunch or dinner) lead to a greater initial and sustained feeling of fullness, increased satiety, and reduced concentrations of the appetite-regulating hormone ghrelin [26–28].
Adequate protein intake is important to protect lean body mass and to increase muscle in response to exercise [8]. Actually, there is little evidence to suggest benefits of high-protein diets on insulin resistance, and a number of studies in women with PCOS have failed to show significant long-term benefits of a high-protein diet on weight loss or insulin sensitivity [16, 29]; there are also concerns about the safety of high-protein, low-carbohydrate diets including the effects of kidney function and bone mineral density [7].
 
6.
Increase food rich in omega–3 essential fatty acids (PUFAs): they have an important role in human cell metabolism; an US study investigated the positive effects of a polyunsaturated fatty acid (PUFA)-rich diet in PCOS patients [28], but further research is required to determine real beneficial and harmful effects of various PUFAs in insulin-resistant populations.
 
7.
Meal timing: the frequency and regularity of eating patterns are important, even if there are small data in the literature.
One of the largest studies [29] conducted revealed that those who ate frequently during the day had higher intakes of carbohydrates, fibers, and a range of micronutrients, while those who ate less frequently had higher intakes of fat, cholesterol, protein, and sodium.
Other studies showed that a regular meal frequency leads to higher postprandial energy expenditure, lower energy intake, and improved impaired insulin sensitivity compared with irregular eating in 2-week interventions [30]. In a further study, breakfast consumption was associated with a lower energy intake and improved insulin sensitivity compared with breakfast omission [31].
 
Data in literature show that a diet with 50 % of total calories from carbohydrates (with a low glycemic index), 30 % from fat (mostly mono- and polyunsaturated fat, less than 10 % from saturated fat), 20 % from proteins, and high in fiber is the most appropriate for patients with PCOS [32].
The optimal frequency of food intake has yet to be determined: however, a regular pattern with low intake from snacks is advisable [8], and high-calorie intake at breakfast with reduced intake at dinner is suggested, because it leads to reduced overall insulin levels [33–35].

6.1.2 Glycemic Index (GI)

It has been shown that eating foods with a low GI improves glucose control in women with PCOS and diabetes.
The glycemic index indicates the rate in which glycemia increases after taking a quantity of “X” food containing 50 g of carbohydrates.
Foods with carbohydrates that break down quickly during digestion and release glucose rapidly into the bloodstream tend to have a high GI; foods with carbohydrates that break down more slowly, emitting glucose more gradually into the bloodstream, tend to have a low GI [2].
The concept was developed by Dr. David J. Jenkins and colleagues [36] in 1980–1981 at the University of Toronto in their research to find out which foods were best for people with diabetes. A lower glycemic index suggests slower rates of digestion and absorption of the foods’ carbohydrates and may also indicate greater extraction from the liver and periphery of the products of carbohydrate digestion.
A lower glycemic response usually relates to a lower insulin demand but not always and may improve long-term blood glucose control and blood lipids [37]. The glycemic index of a food is defined as the incremental area under the 2-h blood glucose response curve (AUC) following a 12-h fast and ingestion of a food with a certain quantity of available carbohydrate (usually 50 g). The AUC of the test food is divided by the AUC of the standard (either glucose or white bread, giving two different definitions) and multiplied by 100. The average GI value is calculated from data collected in ten human subjects. Both the standard and test food must contain an equal amount of available carbohydrate. The result gives a relative ranking for each tested food [38]. The GI Symbol Program is an independent worldwide GI certification program that helps consumers identify low-GI foods and drinks. The symbol is only on foods or beverages that have had their GI values tested according to the standard and meet the GI Foundation’s certification criteria as a healthy choice within their food group. GI cutoffs are listed in Table 6.1.
Table 6.1
Glycemic index cutoffs
Glycemic index cutoffs
High
≥70
Moderate
50–70
Low
<50
Of course, the glycemic index has also its limitations: the index calculations are not accurate because the behavior of foods in different individuals can change, and judging the diet by GI alone does not give the whole portrait of the diet [2].
Moreover, GI values depend on how foods are cooked: cooked carrots have a higher GI than raw carrots because cooking breaks down the fiber and the glucose can be absorbed much more quickly. Cooking with a bit of salt or vinegar may lower the GI of many vegetables because this causes many molecules, not just the sugars, to be broken down, which results in trapping some of the starches in complex structures that are digested more slowly [2].
Furthermore, for some people, a food consumed in the morning on an empty stomach will spike the blood sugar more than the same food eaten later in the day after having breakfast: patients with good blood sugar control in general will show less of a spike in blood sugar than someone with poor blood sugar control [2].
PCOS women should follow some useful GI advices for their daily diet:
  • Eat five to ten different whole fresh fruits, vegetables, and legumes each day.
  • Avoid a diet that consists predominantly of the food highest on the glycemic index.
  • Substitute foods high on the GI with foods lower on the GI: for example, eat boiled green beans (GI of 15) instead of boiled potatoes (GI of 100) with dinner (Table 6.2).
    Table 6.2
    Foods’ glycemic index list
    Foods’ glycemic index
    Sweeteners
    Corn syrup
    100
    Table sugar (sucrose)
    100
    Rice syrup
    65
    Honey
    54
    Fructose
    10
    Stevia
    0
    Grains
    White rice
    90
    Rice cakes
    84
    Wild rice
    81
    Corn chips
    72
    Cornmeal
    70
    Couscous
    65
    Brown rice
    55
    Pop corn
    55
    Whole wheat
    48
    Whole amaranth
    35
    Bread
    Rice bread
    100
    Polenta
    98
    Baguettes
    95
    Doughnuts
    76
    Croissant
    70
    White bread
    70
    Pancakes
    67
    Kamut bread
    54
    Rye bread
    50
    Pasta, whole grain
    44
    Wheat germ
    15
    Cereals
    Instant oats
    92
    Puffed rice
    85
    Grape-Nuts
    67
    Oat bran
    15
    Nuts and seeds
    Chestnuts
    60
    Peanut butter
    40
    Sesame seeds
    35
    Almonds
    15
    Hazelnuts
    15
    Pistachios
    14
    Walnuts
    14
    Peanuts
    14
    Legumes and beans
    Fava beans
    50
    Black beans
    35
    Hummus
    35
    White beans
    35
    Lentils
    29
    Soybeans
    18
    Green beans
    15
    Tofu
    14
    Vegetables
    Potatoes, baked
    100
    Potatoes, boiled
    84
    Carrots, cooked
    80
    Beets, cooked
    64
    Corn
    55
    Peas
    44
    Coconut
    35
    Tomato sauce
    35
    Carrots, raw
    30
    Asparagus
    15
    Cucumbers
    15
    Lettuce
    15
    Mushrooms
    15
    Olives
    15
    Spinach
    15
    Tomatoes
    15
    Zucchini
    15
    Avocados
    10
    Fruits
    Watermelons
    90
    Pineapples
    66
    Apricots
    57
    Strawberries
    56
    Mangos
    55
    Bananas
    52
    Grapes
    50
    Oranges
    46
    Apples
    39
    Peaches
    30
    Raspberries
    25
    Cherries
    25
    Others
    Beer
    110
    Rice milk
    84
    Mango juice
    55
    Orange juice
    45
    Coconut milk
    40
    Soy milk
    36
    Yogurt, low-fat fruit
    33
    Almond milk
    30
    Dark chocolate
    25
    Lemon juice
    20
    Pesto
    15
    Vinegar
    5
    Water
    0
  • Increase fiber intake: fiber helps to slow the digestion of carbohydrates and improves insulin resistance. If a food high on the GI is loved, patient should take care not to consume it often and aim to eat only a small portion of it combined with high-fiber foods that reduce the glycemic index [24, 25].
  • Eat legumes to lower the high-GI foods in the meals: legumes are low on the GI and contain an impressive amount of fiber and good-quality protein, which can serve to blunt the glycemic load. Moreover, legumes contain pinitol, a relative of D-chiro-inositol, noted for improving insulin resistance [2].
  • Avoid overeating foods high on the glycemic index. The GI of a food can be tempered by the quantity consumed. For example, a piece of candy might have a very high glycemic index, but eating just one little piece will not result in a high glycemic load on the body; if the patient eats two pieces of white toast, jam, brown potatoes, and a sugar- or corn syrup-sweetened fruit drink for breakfast, she is putting a high glycemic load on her body, and the blood sugar will remain high for several hours as her body works to process the large amount of high-GI foods [2].
  • Evaluate the whole meat, rather than individual food items, to make sure the patient is preparing meals that will not spike her blood sugars.

6.1.3 Glycemic Load (GL)

Some authors believe that the glycemic load (GL) is a more useful measure of food value than the glycemic index alone.
Glycemic load accounts for how much carbohydrate is in the food and how much each gram of carbohydrate in the food raises blood glucose levels.
GL is a GI-weighted measure of carbohydrate content [39].
$$ \mathrm{GL}=\mathrm{G}\mathrm{I}\times \mathrm{carbohydrate}\left(\mathrm{grams}\right)/100 $$
For instance, watermelon has a high GI, but a typical portion of watermelon does not contain many carbohydrates, so the glycemic load of eating it is low. Whereas glycemic index is defined for each type of food, glycemic load can be calculated for any size serving of a food, an entire meal, or an entire day’s meals.
GL cutoffs are listed in Table 6.3.
Table 6.3
Glycemic load cutoffs
Glycemic load cutoffs
High
≥20
Intermediate
11–19
Low
<10
Foods that have a low GL in a typical serving size have usually a low GI. Foods with an intermediate or high GL in a typical serving size range from a very low to very high GI (Table 6.4).
Table 6.4
Foods’ glycemic load list
Glycemic load (per 100 g serving)
Baguette
15
Banana
16
Potato
20
Carrots
2
Rice
30
Watermelon
4
For detailed information about all the foods, visit the website www.​glycemicindex.​com

6.1.4 Insulin Index

The insulin index is a measure used to quantify the typical insulin response to various foods. The index is similar to the glycemic index and glycemic load, but rather than relying on glycemia levels, the insulin index is based upon insulinemia. This measure can be more useful than either the glycemic index or the glycemic load because certain foods (e.g., lean meats and proteins) cause an insulin response despite there being no carbohydrates present, and some foods cause a disproportionate insulin response relative to their carbohydrate load [40].
Holt et al. have noted that the glucose and insulin scores of most foods are highly correlated, but high-protein foods and bakery products that are rich in fat and refined carbohydrates “elicit insulin responses that were disproportionately higher than their glycemic responses” [40]. They also conclude that insulin indices may be useful for dietary management and avoidance of non-insulin-dependent diabetes mellitus and hyperlipidemia.
Glycemic Index (GI) considers each food relative to eating 100 % glucose, while the insulin index is relative to eating white bread (GI of ~70 to 75) (Table 6.5).
Table 6.5
Foods’ glycemic and insulin index list
 
Glycemic index
Insulin index
Porridge
60 ± 12
40 ± 4
Muesli
43 ± 7
46 ± 5
Cornflakes
76 ± 11
75 ± 8
Average:
59 ± 3
57 ± 3
White bread (baseline)
71 ± 0
100 ± 0
White pasta
46 ± 10
40 ± 5
Brown pasta
68 ± 10
40 ± 5
Brown rice
104 ± 18
62 ± 11
French fries
71 ± 16
74 ± 12
White rice
110 ± 15
79 ± 12
Whole-meal bread
97 ± 17
96 ± 12
Potatoes
141 ± 35
121 ± 11
Eggs
42 ± 16
31 ± 6
Cheese
55 ± 18
45 ± 13
Beef
21 ± 8
51 ± 16
Lentils
62 ± 22
58 ± 12

6.1.5 Exercise

Exercise reduces insulin resistance by two mechanisms. It induces a reduction in visceral fat even if it results in moderate weight loss and BMI reduction [41]. Visceral fat is more metabolically active than subcutaneous fat and central adiposity is more closely related to IR [32].
Exercise, besides, increases muscle cell metabolism: it modulates the expression or the activity of proteins mediating insulin signaling in the skeletal muscles [41, 42].
It has been shown that exercise improves menstrual abnormalities and restores ovulation in obese patients with PCOS [43], and its benefit on reproductive function is greater than the benefit of low-calories diet only [44].
Exercise exerts its beneficial effects on body composition with a 45 % greater reduction in fat mass and a 60 % better preservation of fat-free mass [45].
In fact, it is important to clarify that improved abdominal obesity and insulin sensitivity may occur without a total change in body weight: body composition of patients who exercise regularly may change with increased lean body mass and decreased fat mass, but no overall change in weight [8].
At the moment, there are no guidelines for the type, intensity, frequency, and duration of exercise in patients with PCOS [45, 46].

6.1.5.1 PCOS Exercise Recommendations

1.
Moderate-intensity aerobic physical activity (e.g., brisk walking) for at least 30 min and for at least 5 days per week should be recommended in all PCOS patients [32].
 
2.
Vigorous-intensity aerobic activity (e.g., jogging) for at least 20 min and for at least 3 days per week or combinations of moderate- and vigorous-intensity exercise can also be recommended [32].
 
3.
Resistance training for at least two nonconsecutive days per week [32].
 
4.
Endurance exercise: for patients who cannot manage high-intensity exercise, prolonged lower-level activity is an appropriate way to gain fitness and to increase energy expenditure [8].
 

6.2 Insulin-Sensitizing Agents and Statins

Examining scientific literature, studies are very conflicting to each other, and a unanimous opinion on the effectiveness of insulin-sensitizing drugs has not yet been reached.
According to the ASRM Committee of 2008, insulin-sensitizing agents should be considered in patients with impaired glucose tolerance (IGT) and PCOS [47].
Particularly, in 2010, AE-PCOS Society consensus treatment emphasized that metformin should be used in women with PCOS who have already started lifestyle treatment (diet and exercise) and do not have improvement in IGT or in those who have normal weight but still having IGT [48].
When administered to insulin-resistant patients, these drugs act to increase target tissue responsiveness in order to reduce hyperinsulinemia [49].
In the past, limited studies on the use of diazoxide, acarbose, and somatostatin for PCOS women were conducted; then, thiazolidinediones aroused more interest, while, to date, metformin is the most worldwide studied insulin-sensitizing agent.
Moreover, statins have also been used to improve lipid profile in PCOS women.

6.2.1 Thiazolidinediones

Thiazolidinediones (TZDs) include pioglitazone, rosiglitazone, and troglitazone: during the past, they have been used in PCOS women to reduce insulin resistance.
TZDs are selective ligands of the nuclear transcription factor peroxisome proliferator-activated receptor-γ (PPAR-γ) [50].
They exert their insulin-sensitizing actions by two mechanisms:
  • Promoting fatty acid uptake and storage in adipose tissue
  • Increasing the expression of adiponectin, an adipocytokine with an insulin sensitivity effect [51]
Obese women with PCOS who were administered troglitazone demonstrated benefit in insulin sensitivity, glucose tolerance, and hyperandrogenemia [52–56].
It was demonstrated that even pioglitazone, in doses of 30 mg/day for 3 months, significantly improved insulin sensitivity, hyperandrogenism, and ovulation rates [56].
TZDs were shown to be more effective than metformin in reducing levels of free testosterone and DHEAS after 3 months of treatment, but this benefit was not evident after 6 months of therapy [57].
Pioglitazone is able to produce a significant reduction in the incidence of impaired glucose tolerance and 40 % reversion of previous IGT to normal in PCOS patients treated with 45 mg daily for 6 months [58]. Significant improvements of insulin effectiveness in the liver and skeletal muscle, with substantial increase of circulating adiponectin levels, were also reported [59].
Moreover, some studies demonstrated a clear capacity of pioglitazone to reduce free fatty acid level in PCOS patients, by decreasing lipolysis and increasing lipogenesis [60]; conversely, other studies failed to show any improvement in lipid profile [61].
Additionally, some studies indicate a reduction of inflammatory markers in pioglitazone-treated PCOS women [62], while others do not [58].
A randomized study using treatment with pioglitazone showed that the latter increased ovulation frequency [63]. The regulation of ovulation could in turn restore normal feedback effects of luteal steroids, normalize serum LH levels, and improve ovarian steroidogenesis [64]. Additionally, pioglitazone was shown to ameliorate GnRH-stimulated LH secretion [56].
Administration of pioglitazone during ovarian stimulation period seems to improve ovarian response to controlled ovarian stimulation in PCOS patients, in terms of clinical pregnancy rate, as well as risks of ovarian hyperstimulation syndrome and multiple pregnancies [64].
Previously, TZDs have been accused of inducing weight gain and water retention, but recent studies have disconfirmed this supposition [65].
However, the primary concern with TZDs is the liver toxicity: a significant number of cases of hepatic necrosis were reported in patients using troglitazone, which was withdrawn from the market in 2000.
Pioglitazone safety in women under 18 is not yet established, so it is not recommended in this female PCOS subgroup.
However, in clinical practice, neither pioglitazone nor rosiglitazone is routinely used in PCOS women, especially with infertility issues, because TZDs are classified as pregnancy category C by the FDA, due to the fact that studies in animals have shown adverse fetal effects such as IUGR [64].

6.2.2 Metformin

Despite there is no universal consensus on metformin benefits in PCOS, in this chapter all the beneficial effects of metformin therapy in patients with PCOS are highlighted.
The positive effects of metformin have been demonstrated in nondiabetic women with PCOS, and they are associated with increased menstrual cyclicity, improved ovulation, and reduction in circulating androgen levels [66].
To date neither in Europe nor in the United States metformin has been approved for the treatment of insulin resistance associated with PCOS: its use should be restricted to those patients with IGT [67]; however, it is largely prescribed as an “off-label” drug.
For “off-label” use of any medication, it is extremely important to fulfill several criteria for safe use:
  • The condition should have health consequences significant enough to warrant treatment.
  • The treatment should have demonstrated safety and efficacy.
  • The proposed treatment should be superior to the presently available alternatives [68].

6.2.2.1 Mechanism of Action

Metformin is a second-generation biguanide used as an oral antihyperglycemic agent, and it is approved by the US Food and Drug Administration (FDA) as treatment for type II diabetes mellitus.
It is considered an insulin-sensitizing agent because it lowers glucose levels without increasing insulin secretion, but improving insulin sensitivity.
Metformin causes [69, 70]:
  • Increased peripheral insulin sensitivity, by activating glucose transporters (GLUTs) which allows passage of glucose into hepatic and muscle cells
  • Inhibition of hepatic glucose production
  • Reduction of circulating free fatty acid concentrations, which helps in reducing gluconeogenesis
Metformin activates the adenosine monophosphate (AMP)-activated protein kinase pathway (AMPK) [71, 72]: phosphorylation of threonine in AMPK is necessary for metformin action, resulting in decreased glucose production and increased fatty acid oxidation in hepatocytes, skeletal muscle cells [73], and mouse ovarian tissue [74].
Furthermore, metformin inhibits hepatic gluconeogenesis through an AMP-activated protein kinase-dependent regulation of the orphan nuclear receptor small heterodimer partner (SHP) [75, 76].
Importantly, the actions of metformin are not associated with an increase in insulin secretion and, consequently, with hypoglycemia.
Metformin affects ovarian function in a dual mode:
  • Alleviation of systemic insulin excess acting upon the ovary, particularly on steroidogenesis and follicular growth
  • Direct ovarian effect
Furthermore, metformin acts at the hypothalamic level on AMPK pathway: the latter is essential in the modulation of LH secretion [77].
During the last two decades, some studies demonstrated that metformin inhibits androstenedione and testosterone production from theca cells through inhibition of the steroidogenic acute regulatory protein and 17α-hydroxylase expression [78].
At the ovarian level, hyperandrogenic intrafollicular pattern is improved by a decrease in IGF-1 availability that has an important role in controlling granulosa cell aromatase levels [79].
It has been shown that granulosa cells from women with PCOS have higher levels of FSH receptor (FSHR) expression compared with those from normal ovaries [80, 81].
Metformin reduces FSH-stimulated aromatase expression and activity in granulosa cells; it exerts this action by reducing FSHR mRNA and consequently the activity of FSH (as measured by aromatase expression and E2), without altering cAMP levels. This involves blocking activation of CRE on promoter II of CYP19 via inhibition of pCREB and possible disruption of the formation of the CREB-CRTC2 co-activator complex. This is via an AMPK-independent mechanism [82].

6.2.2.2 Dosage and Side Effects

Metformin is available as 500, 850, and 1,000 mg tablets with a target dose of 1,500–2,550 mg/day.
Metformin has a dose-dependent absorption in humans [83], and its bioavailability is limited to 50–60 % because the amount available may result from pre-systemic clearance or binding to the intestinal wall [83].
Therapeutic regimens of metformin administration are not well standardized, and its dose should probably be adjusted according to the patient’s BMI and insulin resistance [84].
For example, it was demonstrated that nonobese women with PCOS respond better than obese women to metformin treatment at a dosage of 1,500 mg/day for 6 months. Nonobese women, in fact, showed a statistically significant decrease in serum androgen level and fasting insulin level and also an improvement in menstrual cyclicity [85, 86]. Moreover, it is possible that women who did not respond to metformin 1,5 g dose per day might show clinical changes if the dose is increased to 2 g [76].
Common side effects are gastrointestinal, such as diarrhea, nausea, vomiting, bloating, abdominal discomfort, flatulence, and unpleasant metallic taste in the mouth.
Lactic acidosis and hypoglycemia are very rare.
To reduce these side effects, it is recommended to start metformin with a low dose (e.g., 250–500 mg/day) and then gradually increase within a period of 4–6 weeks [76].
Metformin may cause vitamin B12 malabsorption, and so every patient should be monitored for signs and symptoms of vitamin B12 deficiency: numbness, paresthesia, macroglossia, behavioral changes, and pernicious anemia [66].
Metformin prescription should be avoided in women with renal insufficiency, congestive heart failure, sepsis, or hepatic dysfunction [66].
Therefore, testing of hepatic and renal function is necessary in advance of prescription, and thereafter yearly testing is indicated.
However, it has been demonstrated that metformin use for up to 6 months does not adversely affect renal or liver function in a large sample of PCOS women, even those with mildly abnormal baseline hepatic parameters [87, 88].
The length of metformin treatment in PCOS patients is not standardized, but data present in literature [89] showed that, after a long-term metformin treatment, drug suspension is related to a quick reversion of its beneficial effect on peripheral insulin sensitivity.

6.2.2.3 Metformin and Menstrual Disorders

The main complaint about menstrual disorders from PCOS patients is the absence or infrequency of menstrual bleeding.
Few studies noticed the regularization of menstrual cycle after 3–6 months of therapy with metformin alone in 60–70 % of PCOS insulin-resistant patients [90–93] with an important improvement of LH/FSH ratio [90].
The response to the treatment usually depends on the degree of insulin resistance.
The positive effect of metformin on menstrual cycle is commonly attributed to its effectiveness on ovulatory function. However, it is not uncommon to observe discordance between menstrual and ovulatory cycles.
The presence of ovulation should be confirmed through the measurement of luteal phase progesterone levels (usually, levels > 4 ng/mL indicate a previous ovulation) [76].
An Italian study revealed that only 79 % of PCOS women had ovulatory cycles after reaching normal menstrual cycle with metformin treatment [93].
This observation may indicate that the effectiveness of metformin on menstrual cyclicity is probably secondary to a direct effect on the endometrium and not only to an effect on the ovary [67].
Ovulation may be a result of a direct action of metformin on the ovary that leads to normal steroid production and steroid feedback effects that include a lowering of LH and androgen levels [67].

6.2.2.4 Metformin and Endometrium

Excessive insulin levels stimulate endometrial growth [94], and most anovulatory PCOS patients have endometrial vascularization and pattern and thickness abnormalities [95, 96]: PI (pulsatility index) and RI (resistance index) are higher than controls, probably due to the vasoconstrictive effect of androgens on vascular tissues [97].
Metformin may have a positive impact on the endometrium thanks to:
  • Indirect effect: androgen decrease, which leads to the reduction of their vasoconstrictive effects on vascular tissue.
  • Direct effect: insulin stimulates glucose oxidation activity in the late luteal phase in human endometrium; insulin receptors are present at the endometrial level, reaching their maximal expression in the secretory phase. GLUT-4 is an insulin-dependent transporter expressed in the endometrium and involved in endometrium metabolism; GLUT-4 is reduced in PCOS patients, suggesting that in these subjects both insulin resistance and hyperinsulinemia induce an inadequate GLUT-4 expression and so a decreased glucose supply. Thus, by improving hyperinsulinemia, metformin could be effective in restoring endometrial receptivity through a direct effect.
PCOS women who ovulated under metformin treatment showed a triple-line endometrial pattern in a percentage of cases similar to those observed in healthy controls [95], and a triple-line pattern is associated with a significantly higher pregnancy rate.
Another aim of metformin treatment is to reduce the long-term risks of unchallenged endometrial proliferation: hyperplasia and carcinoma.
Their main pathogenic mechanism assumed was hyper-estrogenic stimulation of endometrial growth, unopposed by progesterone. In fact, estrogens act by genetic and epigenetic mechanisms on cancer cells, and a close relationship between estrogens, growth factors, and oncogenes is important in the development of several human cancer [98].
The second hypothesis taken in consideration was the known mitogenic effect exerted by insulin [99].

6.2.2.5 Metformin and Hyperandrogenism

Metformin determines a great improvement on the hyperandrogenism symptoms of patients with PCOS, ameliorating hyperandrogenemia and reducing circulating insulin levels [92, 101–103]. Moreover, as insulin acts as an anabolic growth factor in hair [104], it is possible that the suppression of circulating insulin levels alone may be sufficient to improve the rate of terminal hair growth [76].
A 20–30 % reduction of total and free testosterone, increased SHBG levels, a 30 % decline of androstenedione levels, a modest decrease of FG hirsutism score, and an improvement of acanthosis nigricans were shown [92, 100].
Poor effects on the acne score of young PCOS women were recorded [105].
Several data suggest that metformin could act on hyperandrogenism by interfering both with direct and specific mechanisms on peripheral androgen-secreting organs and with free androgen fraction-regulating systems [67]: in fact, a reduced ovarian and adrenal secretion of androgens, a reduced pituitary secretion of LH, and an increased liver SHBG production seem to be the mechanisms that mediate metformin effect on hyperandrogenism [69].
On the other hand, other studies compared metformin effects to those obtained from oral contraceptives or antiandrogen drugs: the latter achieved a more effective results on hyperandrogenism than metformin alone [106–108].
According to our clinical experience, in overweight/insulin-resistant/hirsute PCOS women, metformin should be considered a first-line treatment, to be associated in combination with antiandrogen therapy.
Moreover, a case reported by an English study group demonstrated how important is the metformin administration even in underweight PCOS patients with menstrual disorder and hirsutism, underlying the essential role of insulin resistance in PCOS pathogenesis, sometimes independent of fat mass or distribution [109].

6.2.2.6 Metformin and Fertility

Metformin reduces insulin levels and alters its effects on ovarian androgen biosynthesis, theca cell proliferation, and endometrial growth; it inhibits ovarian gluconeogenesis, reducing ovarian androgen production [110–112]: all these actions lead to an improved ovulation induction in PCOS patients.
According to the ESHRE and ASRM guidelines issued in 2007, the use of metformin should be limited to patients with impaired glucose tolerance and should be interrupted before the administration of clomiphene citrate, thus restricting the use of metformin to a minority of PCOS patients [113].
However, more recent data suggest that these guidelines should be reconsidered.
Metformin alone has a significant benefit on inducing ovulation in PCOS women, but there is limited evidence that it improves pregnancy rate [101]. According to a multicenter study, metformin alone is not as effective as clomiphene citrate (CC) alone for the treatment of infertility: 55.3 vs. 75.1 % in cumulative ovulation and 7.2 % vs. 22.5 % of life birth [101].
On the contrary, an Italian study stated that the cumulative ovulation rate was similar in women treated with CC or metformin, whereas the pregnancy rate was significantly higher in women treated with metformin [114].
However, metformin is more effective than placebo alone, and it is associated with a significantly lower multiple pregnancy and ovarian hyperstimulation syndrome (OHSS) rate [76].
Because of the lack of evidence, metformin should not be used as first-line monotherapy, but only in those patients who:
1.
Want to improve both metabolic and reproductive functions, but they do not want to immediately get pregnant.
 
2.
Absolutely wish to avoid multiple gestations.
 
3.
Do not tolerate CC or are resistant to CC [76].
Clomiphene resistance is defined as the inability to achieve ovulation after two cycles of clomiphene administration at a dose of 150 mg/day for 5 days [115].
 
4.
Do not achieve a pregnancy (CC failure): metformin could be administered as pretreatment [67].
 
In CC-resistant women, a combined therapy with CC + metformin (contemporarily or as pretreatment) is suggested: in a meta-analysis, this combination significantly improved ovulation and pregnancy rates, decreasing OHSS rate, when compared with CC alone [116].
The percentage of patients with PCOS and clomiphene resistance ranges in the different studies between 15 and 40 % [117, 118]. In these patients, metformin/clomiphene combination induces ovulation in 62.5–77.7 % of cases [116, 119–122].
This result is probably secondary to various mechanisms:
  • Changes in intrafollicular steroidogenesis resulting from the effect of metformin on granulosa cells through an increase in insulin-like growth factor 1 [120]
  • Inhibition of androgen synthesis by the direct action of metformin on the interna theca cells [78]
  • Metformin-induced decrease of adrenal responsiveness to adrenocorticotropic hormone, resulting in reduced adrenal steroidogenesis [123]
  • Reduction in serum LH and prolactin levels resulting from the effects of metformin on the hypothalamic–pituitary axis [124]
Thus, it is possible to state that metformin administration, decreasing insulin secretion, facilitates the induction of ovulation by using clomiphene citrate [125] in patients with PCOS.
The beneficial effects of metformin coadministration during gonadotropin ovulation induction and/or IVF cycles are unclear, and therapy with metformin should depend on the degree of IR.
It is well known that the response of PCOS women to gonadotropin stimulation differs significantly from that of normal ovaries: it is defined “explosive” and it is responsible for the higher risk of canceled cycles and/or for OHSS [126, 127].
In fact, it was shown that during ovarian stimulation, E2 production and E2-to-A ratio are higher in patients with PCOS who have elevated insulin levels than in normo-insulinemic women [126]. Increased insulin levels involve greater ovarian endocrine and morphologic responses to FSH-induced ovulation, which predispose to OHSS.
Therefore, it seems that the typical response of the polycystic ovary to exogenous gonadotropin therapy is related to increased plasma concentrations of insulin [128].

6.2.2.7 Metformin and Pregnancy Loss

Few observational studies have shown that metformin could play an important role in reducing the risk of pregnancy loss [129–131].
In particular, metformin exerts systemic actions by reducing body weight, insulin and PAI-1 levels [131–133], and plasmatic endothelin-1 (ET-1), androgen, and LH concentrations [135] and by increasing IGFBP-1 and glycodelin levels [136].
Moreover, metformin improved the uterine artery blood flow [95, 136] and several endometrial receptivity surrogate markers, as well as endometrial vascularization and pattern [95]. It was hypothesized that metformin might improve perifollicular and peri-corpus luteum vascularization too [95].
Furthermore, in the past, an experimental study [137] demonstrated that metformin also induced AMPK activation within the blastocyst, leading to improved insulin signaling and pregnancy outcomes. In fact, the preimplantation blastocyst stage embryo is an insulin-sensitive tissue, responsive to insulin or IGF-1 via the IGF-1 receptor/translocation of GLUT-4, with an increased glucose uptake [138]. High insulin or IGF-1 concentrations induced a downregulation of IGF-1 receptor [139] with consequent insulin-stimulated glucose uptake reduction, intraembryonic glucose level dropping, and apoptosis triggering [138].
On the contrary, other studies did not confirm these beneficial effects of metformin in preventing abortion [140, 141].

6.2.2.8 Metformin Administration During Pregnancy

The safety of metformin in pregnancy has not yet been established. It crosses the human placenta [142, 143], and it has been detected in umbilical cord blood at levels equal to or higher than the ones in maternal venous blood [144–146]: in fact, except for the first hours after metformin intake, the fetus is exposed to higher concentrations of metformin than the mother [144]. The knowledge on metformin metabolism in the fetus is scarce: it has been hypothesized that part of the metformin is excreted to the amniotic fluid [147] and reabsorbed to the fetal circulation by swallowing. Metformin is then eliminated from the fetus by passage through the placenta into the maternal circulation [144]. Fetal insulin concentrations are not affected by maternal metformin treatment.
A recent study demonstrated that intrauterine metformin exposure seems to result in elevated SHBG levels in newborns [148]. Metformin exposure throughout pregnancy exerts no major effects on maternal or neonatal androgens or estrogens at birth [148].
Metformin is classified as pregnancy category B [149]: a meta-analysis concluded that there was no evidence of an increased risk for major malformations [150].
Additionally, a study demonstrated that metformin did not adversely affect birth length, birth weight, growth, or motor–social development in the first 18 months of life [151].
However, current conservative practice would be to stop treatment once pregnancy has been established, but considering the adverse impact of insulin resistance on the pregnancy, continued metformin treatment after conception in women with PCOS may be beneficial [152].
The rationale of using metformin during pregnancy in PCOS women is the attempt to reduce the risk of developing gestational diabetes and other pregnancy complications associated with insulin resistance, such as preeclampsia.
Metformin seems to reduce the risk of gestational diabetes (GD) [153, 154] that complicates 5–40 % of pregnancy in women with PCOS.
Continued metformin treatment throughout pregnancy appeared to significantly reduce the rate of GDM requiring insulin therapy [155].
The mechanisms recognized in reducing GD incidence were the reduction of preconception weight, insulin, insulin resistance, insulin secretion, and testosterone levels and the persistence of these effects during pregnancy [156].
A less weight gain in women treated with metformin, compared with those treated with insulin, has been reported, and also the incidence of neonatal hypoglycemia was reduced [157, 158].
Furthermore, during the first trimester of pregnancy, metformin seems to influence the trophoblastic invasion of the maternal decidua, myometrium, and blood vessels, allowing a successful placentation with consequent pregnancy outcome improvement, such as prevention of pregnancy-induced hypertension (PIH) and preeclampsia [67].
Increased placental insulin resistance directly impairs nutrient supply to the fetus and leads to fetal growth restriction [159, 160].
Unfortunately, there are only a few studies in literature confirming these preliminary data.
Generally, it is important to note that the beneficial role of metformin in pregnancy-related parameters may be accomplished through a continuum of effects that starts from preconception and lasts throughout pregnancy [152]. In fact, preconception weight loss and IR reduction promoted by the combination of metformin and diet may reduce the likelihood of gestational diabetes in PCOS women [156].
Despite these favorable effects and reassuring clinical data, no definite guidelines recommending metformin use in pregnant women exist: further research is necessary [157, 161].
Finally, it is important to know that metformin is transferred into breast milk in amounts that appear to be clinically insignificant [162–165]. Thus, metformin use by breastfeeding mothers is considered safe. Nevertheless, each decision to breastfeed should be made after conducting a risk/benefit analysis for each mother and her infant [163].

6.2.2.9 Metformin and Metabolic Syndrome

As explained before, metformin increases insulin sensitivity [89, 100, 103, 166–169] and decreases weight, waist circumference, and BMI [100, 102, 167, 170], particularly if associated with diet and physical exercise.
Some authors state that, without metformin, weight loss (through caloric restriction and increased exercise) is difficult to achieve and maintain [171, 172], due to the weight-preserving and anabolic effects of high insulin [173] and androgens [91].
It was demonstrated that reduction of body weight, BMI, and visceral fat was greater than placebo, and the combination of metformin plus lifestyle intervention was more effective than placebo plus lifestyle intervention [174].
Metformin could act to improve body weight in obese PCOS patients both directly and indirectly:
  • Direct effect: on the central nervous system, by modulating appetite in the hypothalamus [175]
  • Indirect effect: via adipocytokine modification
    Visfatin is the most recently identified adipocytokine, which seems to be preferentially produced by visceral adipose tissue and has insulin-mimetic action [176]. Circulating visfatin levels are higher in patients with PCOS than healthy controls, and it was demonstrated that metformin treatment significantly reduced visfatin levels after 3 months of therapy [177].
It has been suggested that weight loss may be a dose-related response with increased weight loss at higher dose [170]. In fact, comparing two different doses, a significant drop in BMI and waist circumference was seen in those patients using the higher dose [178].
Investigators have reported a greater weight, BMI, and WC reduction in obese patients receiving 2,550 mg/day and concluded that the long-term effect of metformin is better with greater dose [170, 179].
Additionally, metformin may slow the progression to type II diabetes mellitus [66].
This protective effect might be associated with the preservation of pancreatic beta-cell function and appeared to be mediated by a reduction in the secretory demands placed on beta cells by chronic insulin resistance [180].
A recent position statement from the AES (Androgen Excess Society) recommended that women with PCOS, regardless of weight, should be screened for IGT or type II diabetes mellitus by an oral glucose tolerance test at their initial presentation and every 2 years thereafter [181].
However, this statement noted that the use of metformin to treat or prevent the progression of IGT could be considered but should not be mandated at this point in time because well-designed RCTs demonstrating efficacy have yet to be conducted [67]. Moreover, it is important to underline that metformin does not maintain its benefits at a biochemical and clinical level after a 12-month treatment suspension [89].
It is widely known that insulin resistance and consequent metabolic syndrome increase the risk of cardiovascular disease: for this reason, it is very important to consider long-term health when selecting a medical treatment in overweight women with PCOS [182].
PCOS young patients usually do not manifest increased blood pressure values [183], but at menopause women with PCOS have a risk of developing hypertension 2.5-fold higher than age-matched controls [184]: metformin could prevent structural changes that precede hypertension [67]. In fact, it has been shown that metformin improve endothelial function, coronary microvascular function, and coronary flow rate [185].
As explained in previous chapters, dyslipidemia is a typical feature of metabolic syndrome: metformin improves hepatic fatty acid metabolism from lipogenesis toward oxidation.
Different beneficial effects are reported on dyslipidemia in PCOS women [130, 173, 186–192]:
  • Decreased total and LDL cholesterol levels
  • Decreased triglyceride levels
  • Increased HDL cholesterol levels
To prevent vascular consequences, LDL particles should be normalized.
Despite metformin has been shown to improve metabolic alteration, it cannot be considered as first-line therapy [193], but it should be used as an adjunct to lifestyle modification.
Besides ameliorating the metabolic syndrome already present, metformin appears to be also effective in preventing the onset of the metabolic syndrome [194]; a study reported that PCOS women treated with a combination of metformin and controlled diet had significant and sustained improvements in all parameters of the metabolic syndrome over 4 years [195]. Conversely, another study showed that beneficial effects of metformin on the metabolic syndrome, without a specific lifestyle modification regimen, could be sustained over 3 years of routine clinic follow-up [194].
Furthermore, chronic inflammation is one of the PCOS features. Metformin alone reduces circulating levels of CRP (inflammation marker that is usually higher in PCOS women) [196]. It exerts a direct vascular anti-inflammatory effect by dose dependently inhibiting IL-1β-induced release of the pro-inflammatory cytokines IL-6 and IL-8 in endothelial cells, human vascular smooth muscle cells, and macrophages [67, 197].
Endothelial dysfunction, assessed by reduced flow-mediated dilatation, has shown promising results in cardiovascular risk stratification and prognosis [198, 199]. Metformin administration for 6 months in women with PCOS induced a significant increase in flow-mediated dilatation that was restored to normal values [200].
A recent study suggests that metformin decreases serum levels of asymmetric dimethylarginine (ADMA) levels, an endogenous inhibitor of NOS, by concomitant effects on insulin action and androgen levels [201].
Metformin seems to be effective even in decreasing AGE levels, which are oxidative mediators of endothelial dysfunction [134].
Plasminogen activator inhibitor-1 is a pro-thrombotic factor produced by the endothelium that inhibits fibrinolysis and regulates vascular smooth muscle proliferation [202]. Insulin upregulates PAI-1 gene transcription [203] and stimulates hepatic [204] and endothelial PAI-1 production [205]. It has been demonstrated that metformin reduces PAI-1 levels [131–133].

6.2.2.10 Metformin and Hypothyroidism

A recent study stated that in overweight PCOS patients with primary sub-hypothyroidism, treatment with metformin (1,500 mg/day) resulted in a significant fall in TSH and in some cases improvement of hypothyroidism [206].
This is an important finding because hypothyroidism occurs in more than 10 % of PCOS patients [207].
Several mechanisms have been hypothesized:
  • A slight increase in the gastrointestinal absorption of levothyroxine (in patients already in treatment with L-thyroxine) [208].
  • Influence of changes in body weight, associated with metformin therapy, on TSH levels [209].
  • Increase of dopamine in the hypothalamus [210]. Previous studies, in fact, have suggested that there was a disruption of the neuroendocrine mechanisms in women with PCOS, mainly due to a deficiency in hypothalamic dopamine [211].
Further studies are needed to confirm these findings, but some authors suggest starting to treat obese PCOS patients with subclinical hypothyroidism with metformin and to reevaluate their thyroid function after 6 months [206].

6.2.2.11 Metformin Use in Lean PCOS Women

It was revealed that metformin decreases ovarian cytochrome P450c17α activity: this mechanism leads to a reduction of free testosterone serum levels even in lean PCOS women, with a consequent improvement of hyperandrogenism [212].
In fact, it has been demonstrated that women with PCOS who have normal weight or are thin responded to a reduction in insulin release with decreased ovarian androgen production and serum ovarian androgens.
As Nestler highlighted several years ago, metformin treatment of nonobese women leads to [213]:
  • Decreased fasting and glucose-stimulated insulin levels
  • Decreased basal and GnRH-stimulated LH release
  • Decreased ovarian androgen production
  • Decreased both serum total and free testosterone concentrations
  • Increased serum SHBG concentrations
  • Decreased androstenedione and DHEAS levels
Six months of metformin therapy clinically results in beneficial effects in lean PCOS women in terms of resumption of menses, without any remarkable effect on metabolic and cardiovascular risk factors [214].
Moreover, a very recent study suggests that treatment with metformin, for at least 12 weeks prior to, and during, IVF/ICSI, is worth considering as a management approach for nonobese women with PCOS [215].

6.2.2.12 Metformin Use in PCOS Adolescents

Metformin is indicated in patients older than 10 years, 2 years after their menarche.
Few studies demonstrated that metformin improved ovulatory function even in PCOS adolescents [93, 216], as well as hyperandrogenism [217].
As in adult population, metformin is effective in reducing hyperinsulinemia and lipid abnormalities.
A recent study reported that PCOS was the main indication for metformin prescription in UK general practice, even if it is off-label [218].
In the FDA approval process, several studies that demonstrated the safety of metformin use in the adolescent population were conducted.
Contraindications and side effects are the same described for adults.
Even if the literature on metformin in adolescents is limited and the number of studies inconsistent, it is possible that early intervention might prevent the complete spectrum of the syndrome in young overweight girls [219].
However, to date, in adolescent population, the first-step treatment is always the lifestyle modification.
In obese adolescents with PCOS, EP combination pills are the standard of care when lifestyle modification is not effective [220]. EP pills treat hyperandrogenism by increasing SHBG and so decreasing free testosterone; it reduces LH and FSH secretion and decreases ovarian stimulation and androgen production. Progesterone induces menstrual cyclicity and prevents endometrial hyperplasia [221]. However, EP pills do not treat IR or components of the metabolic syndrome [222] and are instead associated with glucose intolerance, decreased insulin sensitivity, abnormal lipid profiles, and CV disease [223, 224].
A recent study compared metformin monotherapy vs. estrogen–progesterone + metformin in the treatment of overweight and obese PCOS adolescents [220]: it was shown that the use of metformin alone was associated with greater decrease in total cholesterol and triglycerides and with a better improvement in weight loss.
These findings suggest that metformin monotherapy is more effective in reducing cardiovascular risk in overweight and obese adolescents with PCOS than the combination with EP pill [220].

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Related posts:

  1. Introduction
  2. Psychological Implications of PCOS
  3. Clinical Features
  4. Diagnosis and Assessment

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Jun 25, 2017 | Posted by in GYNECOLOGY | Comments Off on PCOS Therapy

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